Traditional animation isn't making a comeback because it never went away. Persepolis and The Triplets of Belleville were both hand-drawn and traditionally animated. Plus, as was pointed out above, Disney has hand-drawn features in the wings.
On a similar note, CGI isn't going anywhere either; it's considered the latest thing right now, but eventually the novelty will wear off, and we won't see as many CG films as before, but the medium won't be coming to an end either. Both are just different ways of telling a story, and there's no reason that both styles can't peacefully co-exist.